Excellent game! Not much to say about this one. I loved the mechanics of upgrading all the pets and seeing all the great sprite work you did! I do think at times it got a little repetitive, but I think you could fix that pretty easily with some minor tweaks. In particular, I think making bulk purchases slightly cheaper would give the player a reason to look forward to the next "unlock" in the shop. The tree upgrades are also way more powerful than the pet upgrades, which if you figure that out, you basically just spend the whole game buying "fertillizer". I actually managed to upgrade the tree so much I got negative cash XD.
This is all really minor feedback though - overall I think this game was really well put together. The twist at the end was really cool to see too!